fharp roftrum and head, whence they enter by the smallest aperture or excoriation, nay by the very pores of the skin, like mercury. Now let us fuppofe, that a male and female louse have got into one of these paffages, and have lodged betwixt the cutis and cuticula at some distance, no paffage will appear to the naked eye. These vermin will multiply, as we remarked before, and all their progeny will remain in the fame place, whence this tumour will arise, as Valifneri has frequently observed in paralel cafes; for feeing a perfon, who by scratching a small tumour had extracted many vermin out of it, the author remarked, and clofely obferved, that the feveral tumours of this kind, which the patient afterwards had, fprung from the ingrefs only of two lice into thofe parts betwixt the cuticula and cutis. Several inftances of the like diforders in other animals may be cited. Into the fkin, for inftance, of cows, fmall flies enter in the fummer time, which ingender in it, and appear the following feafon. Thus in all cornuted animals are frequently feen feveral flies, which enter into the finus frontales in fummer, and there produce fmall

worms,

worms, whence fpring flies in the following fummer. Thus far of this theory'; now of what is more medicinal.

SYMPTOMS. As the fymptoms of this diforder are few and easily discovered, their detail will be short. The infant has a continual

itching of the head, from the irritation produced by the many feet of these animals when they creep, and from their pointed sharp mouths. Hence fpring perpetual agitation, uneafiness, and raising the hand every inftant to scratch the head; fo that the impreffions may at last become painful, especially if the parts be excoriated, as in the Crufta lactea, &c. These symptoms being a little more intenfe, produce watchings, and at length a flight fever, which, by the obftinacy of the evil, and the exulceration of the part, being thus fomented, may at laft degenerate into a flow fever, marafumus, and perhaps death.

DIAGNOSTICS. Nothing is easier than to know the existence of a Phthiriafis from the description and symptoms of the disorders above explain'd, from the greater or leffer number of vermin, the crufta lactea, &c. which accompany it, and which by the constant ir

ritation

ritation, punction, and acrid fæces of thefe animals, produce a malignant and obftinate quality.

PROGNOSTICS. To be fhort, this diforder is feldom mortal, if the irritation be not fo intense as to exafperate the tinea, crusta lactea, fcabies, or other excoriation, to fuch a degree as to produce a flow fever and marafmus.

: CURE. The remedies employed in this cure, are internal or external. The internal remedies should chiefly tend to correct the peccancy of digeftion, to create a laudable chyle, and prevent the fpiffitude of the humours: for this intent, let the child be purged now and then, as once a month, by the fyrup of peach-bloffoms, white rofes, compound fuchory with rhubarb, and cathartic fyrup of apples, to an ounce or two of any of them ; and you may add, occafionally, two or three spoonfuls of the infufion of rhubarb, or of fenna; the cathartic syrup of apples, with the infufion of fenna, are employed for the ftronger fort of children. The fyrup of peach-bloffoms, or compound fuchory, as occafion requires, are the next. The following powder is very much cele

brated

V

brated for this purpose, it confifts of abforbent remedies,

R Corall, rubr. pp. ocul. cancr. pulv. viper. aa p. x. m. f. omnium pulv. cujus dofis fingulis, dieb. aut altero quoque die fit ad XV, aut xx. gr.

Take of prepared red coral, crabs eyes and powder of vipers, each equal quantities: reduce all to a powder, of which fifteen or twenty grains are to be taken every day, or every other day.

Combing and washing the child's head, and taking all the other pains of that kind are useless, without the topical remedies: these are lotions, fomentations, unctions, powders, fumigations.

1. The lotions are made with a decoction of the roots of the round birth-wort, or elicampane, or briony; of each an ounce; to which add the leaves of purslain, wild mercury, fopewort, of each a fufficient quantity, these you boil in two or three quarts of water, to the consumption of a pint, and wash the patients head therewith,

dipping

dipping a piece of linen in it, and applying the fame to the affected part. To render this lotion the more efficacious, if the patient can bear it, diffolve therein a fmall quantity of fea-falt, or falt-armoniac, or nitre; for these falts not only cleanse the head, but contribute to kill the vermine: and though they irritate much in the beginning, yet by degrees the child may become fo accustom'd to them, as to bear them easily.

2. If the preceding remedies will not do, you may have recourfe to unctions, with proper liniments applied to the parts most affected. Let them be thus made:

R Sulph. commun. 3j. ol. commun. vel laurin. q. f. bull. ad confift. ungent.

Take of common fulphur one ounce, and of oil of olives, or of bays, a fufficient quantity, boil up to the confiftence of an ointment.

With this the patient's head should be anointed. It is tenacious, and will adhere to the head; whence its effect will hold the

longer or you may make your liniment